A gas chromatograph is configured such that a sample vaporization portion is connected to one end of a separation column and a detector is connected to the other end of the separation column. The sample vaporization portion is to allow a sample gas obtained by an injected sample being vaporized to be introduced into the separation column by a carrier gas. The sample gas introduced into the separation column is temporally separated by component and each sample component is detected by the detector.
Temperature control is performed with the separation column accommodated in a column oven. The sample vaporization portion and the detector are attached to the upper surface of the column oven or the like and integrated with the column oven. The column oven is covered with a heat insulating material, and the inside and the outside of the column oven are thermally blocked from each other (see, for example, Patent Literature 1).
The detection sensitivity of the detector has a high level of temperature dependence as well, and the detection sensitivity is disturbed and the reproducibility of an analysis result is deteriorated once the temperature of the detector fluctuates. Accordingly, a detection unit of the detector performing the sample component detection is disposed outside the column oven and temperature control on the detection unit is performed independently of the column oven.
[Patent Literature 1] JP-B-7-18850